CT scan risks

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:How does anyone know that a cancer several years after ct scans has to do with CT scans? Sounds correlative, but not necessarily causal. There's many reasons for cancer, both environmental and genetic.

If you have a large enough sample size and account for other factors as well (family history, exposure to pesticides, etc) you can do things like a regression analysis to get a sense of it's just a correlation or it make be more causative. Also, you can look at the correlations with those other factors. These machines have been around for long enough I assume the studies have a fairly large sample size. Studies have to be pretty rigorous to make it into peer reviewed journals.

Can anyone cite a refereed article on this question?

I have access to a good research library, so access to a reputable article should not be a problem.

BMC Cancer, 2022 Nov 30;22(1):1238. doi: 10.1186/s12885-022-10310-2.
CT Scans and Cancer Risks: A Systematic Review and Dose-response Meta-analysis

Conclusions: Based on 111.6 million adult participants from 3 continents (Asia, Europe and America), this meta-analysis identifies an inordinately increase in cancer risks from CT scans for adults. Moreover, the cancer risks were positively correlated with radiation dose and CT sites. The meta-analysis highlights the awareness of potential cancer risks of CT scans as well as more reasonable methodology to quantify cancer risks in terms of life expectancy as 100 years for LAR.

Lancet, 2012 Aug 4;380(9840):499-505. doi: 10.1016/S0140-6736(12)60815-0. Epub 2012 Jun 7.
Radiation exposure from CT scans in childhood and subsequent risk of leukaemia and brain tumours: a retrospective cohort study

Interpretation: Use of CT scans in children to deliver cumulative doses of about 50 mGy might almost triple the risk of leukaemia and doses of about 60 mGy might triple the risk of brain cancer. Because these cancers are relatively rare, the cumulative absolute risks are small: in the 10 years after the first scan for patients younger than 10 years, one excess case of leukaemia and one excess case of brain tumour per 10,000 head CT scans is estimated to occur. Nevertheless, although clinical benefits should outweigh the small absolute risks, radiation doses from CT scans ought to be kept as low as possible and alternative procedures, which do not involve ionising radiation, should be considered if appropriate.

Eur J Trauma Emerg Surg, 2018 Feb;44(1):19-27. doi: 10.1007/s00068-016-0665-6. Epub 2016 Mar 24.
Cumulative radiation exposure and estimated lifetime cancer risk in multiple-injury adult patients undergoing repeated or multiple CTs

Conclusions: More than half of the multiple-injury trauma patients were classified as low risk cumulative effective dose (≤20 mSv) and almost all patients had a low LAR risk of cancer incidence from CT studies. Patients who were at the highest risk of cancer from CT scans were those aged under 30 years who had multiple or repeated scans, particularly in the trunk.

[Anonymous]

^^

https://pmc.ncbi.nlm.nih.gov/articles/PMC9710150/

https://pmc.ncbi.nlm.nih.gov/articles/PMC3418594/

https://link.springer.com/article/10.1007/s00068-016-0665-6